strudel-groove

name: strudel-groove description: The craft of rhythm and groove in electronic music — why a beat feels good (or stiff). Covers swing/shuffle, the pocket, drum programming by genre (house, techno, hip-hop, jungle/DnB), ghost notes and velocity dynamics, humanization vs. quantization, polyrhythm and polymeter via Euclidean patterns, and the kick-bass lock. Use when the beat feels stiff or robotic, the drums need life, you want to add swing or shuffle, you're programming a drum pattern for a specific genre, or anything about ghost notes, groove, velocity, feel, pocket, polyrhythm, or making drums human.

Groove is not a setting. It is a system. Swing alone won't save a rigid beat. You need timing variance + velocity dynamics + smart placement working together.

Why Beats Feel Good (the physics)

• Syncopation creates tension. Notes landing between the grid set up resolution — the brain anticipates the downbeat and the off-hit releases it. No syncopation = no conversation with the listener.
• Velocity asymmetry is the single biggest lever. A flat-velocity pattern sounds mechanical even with perfect timing. Real drummers anchor the backbeat hard and ghost the 16ths soft.
• Slight lateness = relaxed. Research rates micro-late events as more "groovy" than micro-early. Pull the snare 10–15ms late for pocket; push early for urgency (neurofunk: 5–8ms ahead on hats).
• The pocket is a relationship, not a property of a single voice. Groove lives in the interaction between kick, bass, and snare — particularly where the bass note starts and ends relative to the kick.

Swing — the numbers that actually matter

Swing delays every second 16th note within each 8th-note pair. The math:

• 50% = straight (no swing)
• 66% = perfect triplet swing (jazz hi-hats, shuffle)
• 54–62% = house/hip-hop sweet spot — enough movement without obvious shuffle
• 58–65% = heavier hip-hop/boom-bap, 90s MPC feel

Don't apply swing globally. Swing the hats and snare; leave the kick and bass on-grid. A swung kick in 4/4 house sounds drunk, not groovy.

In Strudel — swingBy(amount, subdivision):

// amount 0 = none, 0.5 = half the 16th-note spacing, 1/3 ≈ triplet swing
s("hh*8").swingBy(1/3, 4).bank("RolandTR909")
// swing(N) is shorthand for swingBy(1/3, N)
s("hh*16").swing(8).bank("RolandTR808")

Use .late(n) / .early(n) to nudge individual voices in cycles (not ms) — stack voices then offset one:

stack(
  s("bd*4"),
  s("~ sd ~ sd").late(0.005)   // snare just behind the grid
).bank("RolandTR909")

Velocity & Dynamics — the most neglected dimension

A flat-velocity kit is the #1 sign of amateur programming. Hierarchy:

• Kick / snare accents: 80–100% (the anchors)
• Regular hats: 50–70%
• Ghost notes: 20–40% — present but not calling attention
• Off-beat accents (the "and" of beats): 60–75%

In Strudel, .gain("...") is your velocity sequencer. Pattern it explicitly:

// hi-hat groove: ghost ghost ACCENT ghost ghost ACCENT ghost ACCENT
s("hh*8").gain(".3 .3 1 .3 .3 1 .3 1").bank("RolandTR909")
// snare with ghost note on the 16th before beat 3
s("~ [hh:ghost sd] ~ sd").gain("1 [.3 1] 1 1").bank("RolandTR909")

Ghost Notes

A ghost note is a very quiet hit on a "wrong" beat — typically a snare ghost on the 16th note before a backbeat, or hats between the main grid. It fills negative space without adding weight.

• Place ghosts at velocities 20–40% — audible but not a hit
• One or two per bar is enough; more becomes clutter
• The ghost → accent pairing (ghost then hard hit on the next 16th) is the J Dilla signature

Genre Patterns — placement rules

House (120–130 BPM)

• Kick: 4-on-the-floor, occasionally doubled on the "and" before beat 1
• Snare/clap: 2 and 4, sometimes with ghost 16ths
• Hi-hat: 8ths or 16ths; open hat on the "and" of 2 or 4
• Swing: heavy (54–62%) on hats and snare; kick straight

s("bd*4, [~ cp]*2, [~ hh]*4, oh:2(1,4,2)").bank("RolandTR909")

Techno (130–150 BPM)

• Kick: 4-on-the-floor, harder and longer transient than house
• Snare: often absent or buried under clap reverb; accent on 3 (not 2+4)
• Hi-hat: sparse, rides and open hats; synths carry the top end
• Swing: minimal to none — rigidity is part of the aesthetic

Hip-Hop / Boom-Bap (85–95 BPM)

• Kick: syncopated, often on the "and" of beats; rarely 4-on-the-floor
• Snare: 2 and 4 with intentional micro-lateness; ghost notes liberally
• Hi-hat: 16ths with heavy velocity variation; triplet rolls on fills
• Swing: 58–65% MPC feel; entire kit swings together (exception to the "don't swing globally" rule — in hip-hop the whole machine swings as one)

Jungle / Drum & Bass (160–180 BPM)

• Built from chopped-up breaks (Amen, Think, Funky Drummer)
• Kick: on the 1 (or between 1 and 2); snare the critical anchor
• Ghost-snare before the backbeat is essential for the rolling feel
• .chop(16) or .slice(8, "...") on break samples → see [[strudel-pro-tips]]

Euclidean Rhythms — the shortcut to interesting patterns

Euclidean rhythms spread N hits across K steps as evenly as possible. They encode most of the world's great timelines mathematically:

• (3,8) = the Cuban tresillo / fundamental offbeat pattern
• (5,8) = son clave basis; 5-beat feel over 8 steps
• (3,4) = standard quarter-note triplet
• (5,16) = bossa nova bass pattern
• (7,16) = dense syncopated pattern (afrobeat feel)

In Strudel — inline syntax s("bd(3,8)"):

// Polyrhythm: kick on 3, hat on 8, snare on 5 — all cycling independently
s("bd(3,8), hh(7,8), sd(2,8,2)").bank("RolandTR909")
// Offset parameter rotates the pattern: (3,8,0) vs (3,8,2) shifts phase
s("bd(3,8,0), rim(3,8,3)").bank("RolandTR808")  // offset 3 creates the call-and-response

Polymeter: use patterns of different lengths in parallel — they phase against each other. A 3-step pattern against a 4-step pattern cycles every 12 steps, creating long-range variation with minimal programming.

Polyrhythm vs. Polymeter

• Polyrhythm: two rhythms complete in the same time (3 against 4 lands on the same downbeat). Unstable, dramatic.
• Polymeter: different-length patterns run simultaneously; downbeats phase. Hypnotic, evolving — what Strudel's Euclidean layering naturally produces.

(3,8) kick over (4,8) hat = polymeter that realigns only every 24 steps. Simple pattern, 12-bar variation for free.

The Kick-Bass Lock — groove lives here

The kick and bass must agree in time and frequency:

• Rhythmically: the bass note onset should land with the kick or just after (3–10ms late) — never ahead. A bass note that anticipates the kick breaks the pocket.
• Melodically: bass note on kick = root or 5th. Notes between kicks can move, but the kick-beat note anchors tonality.
• Duration: shorten bass notes on kick beats — staccato bass on the kick hit, then sustain between. Long decaying bass notes mask the kick's punch.
• Frequency: in electronic music, kick and bass share the 60–100 Hz sub range. One of them owns that band per moment — the kick's transient punches through, then the bass takes over. Side-chain compression automates this; compositionally, write the bass to release when the kick hits.

Common Mistakes

• All notes same velocity: the fastest path to "robotic." Even three gain values (loud / mid / quiet) is transformative.
• Swing applied to everything: swinging the kick in 4/4 dance music sounds wrong. Swing the mid-layer (hats, snare) and leave the kick straight.
• Ghost notes at full volume: a ghost at 80% is just a hit in the wrong place. 25–35% is the useful range.
• No syncopation in the hat layer: 8ths-on-the-downbeat hats with nothing on the offbeats is the most common cause of "stiff" patterns. The "and" of beats is where momentum lives.
• Bass ignores the kick: a syncopated bassline with no rhythmic relationship to the kick pattern creates a muddy low end with no pocket.
• Humanizing with timing only: timing variation alone sounds sloppy. Combine it with velocity variation for "human" rather than "drunk."

Humanization vs. Quantization — when to use each

• Full quantization: techno, minimal house, anything where rigidity is the aesthetic. Keep it. Don't fight the grid.
• Light humanization (5–10% velocity spread + 1–2ms timing nudge): house, hip-hop, most grooved electronic. Enough life without losing tightness.
• Heavy humanization / off-grid: boom-bap, jazz-influenced, broken-beat. Entire kit may swing together; timing wanders intentionally.

In Strudel, layer sometimesBy and gain patterns rather than adding a "humanize" monolith:

s("hh*8")
  .gain(".4 .6 1 .4 .5 1 .35 .9")   // explicit velocity curve
  .sometimesBy(.15, x => x.late(.004)) // occasional micro-late
  .bank("RolandTR909")

See also: [[strudel-compose]] (section/stack architecture), [[strudel-arrangement]] (when to introduce the groove), [[strudel-pro-tips]] (break-chopping, .off(), humanize probability), [[strudel-modifiers]] (.late(), .early(), .swingBy(), .ply() full docs), [[strudel-sample-library]] (bank names, drum kits), [[strudel-sound-design]] (layering kick transients), [[strudel-mixing]] (kick-bass frequency management), [[strudel-harmony]] (bass-kick note choices), [[strudel-melody]] (rhythmic placement of melodic lines).

Sources: Roger Linn on Swing — Attack Magazine · DAW & Drum Machine Swing — Attack Magazine · Drunk Drummer Grooves — Attack Magazine · Swing, Shuffle & Humanization — SampleFocus · Drum Programming Guide — LANDR · EDM Drum Programming Guide — EDMProd · Euclidean Rhythms — LANDR · Strudel Time Modifiers · Strudel Mini-Notation · Polyrhythm & Polymeter — MysticAlankar · Kick-Bass Relationship — Hyperbits